Some people say that computer is one of the most important inventions of all time. Computer really makes our life easier. Not only it can serve as a personal entertainment, it also works as powerful work station all in one. However virus and spyware most of the time prevents a computer system to work on its full potential. How does virus and spyware enter your computer? How can we prevent our precious system from getting infected, and doing manual virus removal?
A virus can enter in your system when:

When you open an infected email attachment.
When you use an infected USB storage device.
Downloading a file with infection from the internet.
A spyware can get in your system when:
You click OK on pop up messages without reading it thoroughly what is it all about.
You go to adult sites or port sites.
You install a program without reading what the free programs that installs with it are.
First line of protection against infection will be anti-virus and anti-spyware program. First this will automatically scan information going into your computer while surfing the internet or while you transfer files using USB storage device or optical media. It will warn you if there is a possible threat being detected. It is also critical for you to do a virus or spyware scan twice a week, in order to detect possible infection that is just lurking in your system. Another is windows firewall or hardware firewall. It should always be present and constantly turned on, in order to prevent hackers from accessing you computer remotely to steal some credit card or bank information. Most of the routers today not only shares internet connection, it also serves as a firewall.
The steps above should help you avoid doing manual virus or spyware removal however there are occasions that even with this protection in place. The computer still gets infected with virus or spyware, and if you are lucky enough it could be infected by both. Most of the time if the infection went through the spyware or virus protection that you have, doing a scan will not help anymore. This means that your protection program is oblivious of the pending danger. In this case you only have two options. Backup your files and reformat or erase everything in your computer and start with a clean slate or hire a technician to do manual virus and spyware removal.